American swimmer Michael Phelps has set another world record at the World Swimming Championships in Melbourne, Australia - but he needed some help from his teammates to do it.

Phelps was part of the U.S. men's 4 x 200 meter freestyle relay team that set a new mark of 7:03.24. The time was nearly 1.5 seconds faster than the old mark set by Australia in 2001. Phelps has now won five gold meals and set four world records in this championship.

Earlier, Phelps's teammate Ryan Lochte set a world record in the men's 200-meter backstroke, finishing in 1:54.32. The time broke the old mark set by world and Olympic champion Aaron Peirsol last year. Peirsol was second Friday while Austria's Markus Rogan (1:56.02) won the bronze.

In women's action, Australia's Libby Lenton won the women's 100-meter free-style sprint in 53.4 for her second gold medal of the meet. Another Australian, Leisel Jones, won the women's 200-meter breaststroke gold medal in two minutes, 21.84.